Fittkauimyia carranquensis, Dantas, Galileu P. S. & Hamada, Neusa, 2013

Dantas, Galileu P. S. & Hamada, Neusa, 2013, Two new species of Fittkauimyia Karunakaran (Diptera: Chironomidae) from Brazil, Zootaxa 3681 (5), pp. 573-582 : 578-581

Fittkauimyia carranquensis new species

( Figs. 4 –6)

Type material. Holotype, male with pupal exuviae, Brazil, Minas Gerais State,Carrancas municipality, Pousada Sete Quedas, 21º 27'56.3"S, 44º 38'40.6"W, 20/v/2012, in decayed leaves, G.P.S. Dantas, N. Hamada and L.M. Fusari ( MZUSP, slide mounted in Euparal®).

Diagnosis. The male of F. carranquensis sp. n. can be separated of all other species of the genus by the combination of iridescent eyes, acrostichals confined to the part anterior to the scutal tubercle, number of setae on tibial comb and pigmentation of the abdomen. The pupae can be distinguished by the combination of anal lobe fringe on both inner and outer border, lateral fringe with about 12 setae at the anterior half of segments II and 8–11 LS setae on segment VIII.

Etymology. Named after the type locality, Carrancas municipality, Minas Gerais State, Brazil.

Male (n = 1). Total length 4.74 mm. Wing length 2.62 mm. Total length/ wing length 1.81. Wing length/ length of profemur 2.01.

General coloration brownish. Eyes iridescent. Head, antennas and wings brownish, thorax and legs brown. Abdomen: T I pale, anterior half of TII–VII with three areas of brown pigmentation, one central and two lateral, TVIII with two lateral areas of brown pigmentation, hypopygium brown ( Fig. 4 D).

Head ( Fig. 4 A). AR 1.86. Thirteenth flagellomere 868 µm long. Apical flagellomere 87 µm long; 23 µm wide. Temporal setae 17. Clypeus with 19 setae. Tentorium 251 µm long. Palpomere lengths (1–5 in µm): 51; 56; 107; 213; 319.

Thorax ( Fig. 4 B). Scutal tubercle present. Acrostichals 18, distributed between the anterior end of the scutum and the scutal tubercle; dorsocentrals 23, in a single irregular row; prealars 10, in a Y-shape arrangement. Antepronotum with 3 setae. Scutellum with 17 setae, in two rows. Postnotum with 4 setae. Haltere with 14 setae.

Wing ( Fig. 4 C). VR 0.91. Membrane with dense covering of macrotrichia except for cells r, m, r 2+3 and cu; C produced beyond apex of R4+5. Brachiolum with 8 setae. All veins with setae except for M-Cu. Squama with 21 setae.

Legs. Spur of fore tibia 77 µm long, with 25 teeth; spurs of middle tibia 56 µm long, with approximately 12 teeth and 85 µm long, with 25 teeth; spurs of hind tibia 68 µm long, with 18 teeth and 70 µm long, with about 19 teeth. Tibial comb of 12 bristles on hind leg, the lateral larger than the central. Claws of fore and hind legs normal, sharply pointed; claws of middle leg spoon-shaped; pulvilli present. Lengths (in µm) and proportions of legs as in Table 3 .

Hypopygium ( Fig. 5 A). Gonocoxite elongated, subcylindrical; 252 µm long; 96 µm wide; dorsal swellings well developed and setigerous. Gonostylus 143 µm long; with bristles along inner margin and in dorso-apical area, base covered by hair; megasetae 15 µm long. HR 1.76; HV 3.31.

Pupa (n = 1). Total length 6.55 mm. Coloration: cephalothorax and abdomen brown.

Cephalothorax. Thoracic horn (Fig. 6A) 542 µm long and maximum width 240 µm; plastron plate 87 µm long, 117 µm wide. Thoracic membrane granulose.

Abdomen (Fig. 6C). Tergite I without shagreen; tergites II–VII with field of fine shagreen on central area; tergite VIII with large field of shagreen; genital sac of male with shagreen on basal half; shagreen spinules short, pointed distally, solitary or serially arranged in short transverse rows. Tergite I with 4 pairs of small D-setae, tergite II with 5 pairs of D-setae, these setae short and taeniate not represented in Fig. 6C. D1-setae somewhat taeniate on tergite III, 174 µm long; sclerotized and spiniform on tergite IV–VII, 114, 120, 112 and 138 µm long respectively, all arising from a more or less distinct tubercle; basal tubercle of D1-seta large and with sclerotized beak on tergite III and IV (Fig. 6B). D2- and D3-setae very long and arising from large tubercles on tergite III and IV (Fig.6B), short and not arising from tubercles on tergites V–VII, all taeniate. D4- and D5-setae short and taeniate on tergites III–VII. Segments I–VI with 2 pairs of taeniate L-setae, segment VII with 1 pair of taeniate L-setae, segment VIII with 8–11 taeniate L-setae. Lateral fringe with about 12 setae at the anterior half of segments II; with about 20–32 setae at the anterior half of segment III; about 65–100 setae along each entire lateral margin of segments IV–VII; segment III with a single additional setae in posterolateral corner. Anal lobe 502 µm long, wide not measurable because the anal lobe is damaged in the material examined (Fig. 6C). Male genital sac 132 µm long.

Female and larva unknown.

Systematic remarks. The male imago of F.carranquensis sp. n. is similar to F. crypta and F. nipponica by having acrostichals distributed anterior to the scutal tubercle, iridescent eyes and well-developed antepronotum. However, it can be differentiated of F. crypta by the number of setae on tibial comb, number of acrostichals, values of LR and by the abdominal pigmentation. The last feature also distinguishes F. carranquensis sp. n. from F. nipponica . The pupa of F. carranquensis sp. n. resembles the pupa of F. crypta , but can be separated from this species by having 8–11 LS setae on segment VIII, while F. c r y p t a has 16–21.

Notes on species biology. The specimen of Fittkauimyia carranquensis sp. n. was obtained from a pupa collected in decayed leaves accumulated on the bottom of a small stream. The stream where the specimen was collected has the following characteristics: altitude of 1140 m, temperature of 16.8 C, pH of 8.2 and conductivity of 3.7 μScm -1.

FIGURE 6. Fittkauimyia carranquensis sp. n. Pupa. A. Thoracic horn. B. Basal tubercle of D1-seta with sclerotized beak (left) and base of D2- and D3-setae (right) with large tubercles on tergite III. C. Abdomen, in dorsal view (anal lobes damaged).

Figures

FIGURE 4. Fittkauimyia carranquensis sp. n. Adult male: A. Head. B. Thorax. C. Wing. D. Abdomen.

Tables

TABLE 3. Lengths (in µm) and proportions of leg segments of Fittkauimyia carranquensis sp. n. male (n = 1).

Fe	Ti	ta1	ta2	ta3	ta4	ta5	LR	BV	SV	BR
P1 1289	1571	1535	631	490	315	131	0.98	2.80	1.86	3.71
P2 1477	1466	1414	611	410	245	120	0.96	3.14	2.08	2.97
P3 1482	1748	1383	584	508	367	143	0.79	2.88	2.33	3.86